CNC Tolerance Calculator
Select your process, feature, dimension, and material to instantly compute achievable tolerances, IT grades, surface roughness, and ISO fit recommendations.
Ginwate CNC
Tolerance Calculator Report
12 October 2026
Calculation Inputs
Process: CNC Milling
Feature Type: External Diameter / OD
Nominal Dimension: 25 mm
Material: Aluminum
Tolerance Class: ISO 2768-f (Fine)
Parameters
Range: 0.1-1 000 mm
Achievable Tolerance Band
IT Grade: IT8
Standard precision: general engineering fits, motor housings, typical CNC machined components.
Surface Roughness Achievable
Ra 0.4-1.6 μm
ISO Fit Recommendations
Cost Impact
+15-30% vs. standard
Common Tolerance Requirements by Industry
| Industry | Typical Tolerance | IT Grade (approx.) |
|---|---|---|
| Aerospace | ±0.005 mm | IT5 |
| Medical / Implants | ±0.010 mm | IT6 |
| Automotive (precision) | ±0.020 mm | IT7 |
| General Engineering | ±0.050 mm | IT8 |
| Consumer / Structural | ±0.100 mm | IT9 |
* Values represent typical achievable tolerances. Actual capability depends on part geometry, material, batch size, and feature location. Contact Ginwate CNC for a DFM review on critical dimensions.
ginwatecnc.com · Precision CNC Machining
This report is an estimate. Contact us for a full DFM review.
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